The report, based on analysis from the Office for National Statistics's opinions survey, looked at factors associated with age discrimination and prejudice, and compared attitudes between people in their 20s and those aged over 70.

Perceptions towards those aged over 70 were more positive than towards those in their 20s, with older people viewed as being more friendly, having higher moral standards and as being more competent than their younger counterparts.

However, when respondents were asked how acceptable they would find a suitably qualified 30-year-old or 70-year-old boss, the results showed a bias towards younger workers. While most were accepting of either age, three times as many (15% and 5% respectively) thought that having a 70-year-old boss would be "unacceptable" compared with having a 30-year-old boss.

On average, respondents thought "youth" ended at 41 and "old age" began at 59. However, this varied by as much as 20 years in relation to the age of the respondent: the age at which youth stopped and old age started increased in relation to the age of the respondent.

"We have seen a very high instance of age-related unfairness, particularly when people are selected for a new job or promotion only if their 'face fits', which unfortunately means some people feel that talent isn't enough to overcome such prejudices," Keating said.

"While many companies have solid diversity policies, this may not run throughout the company, which is an issue that needs to be addressed. It is important that employers do all they can to ensure this does not lead to discrimination or favouritism of any kind, which could cause the exclusion of talented individuals from the workplace."

Just over a third of respondents said they had seen some age-related prejudice in the past year. Experiences of age discrimination were more common for younger groups, with under-25s at least twice as likely to have experienced it than other age groups.

In general terms, people in their 40s were viewed as having the highest status, while on average people aged over 70 were given a higher status than those in their 20s.

Keating urged employers to renew their commitment to building age-diverse workplaces. "We work with many companies who removed the mandatory retirement age a long time ago and have all reaped the benefits of employing a multi-age workforce," she said.

"They know that variation in the workforce brings fresh ideas and perspectives from which companies will always benefit. Ultimately, forward-looking employers know that age diverse workforces are effective, productive and motivated."

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